The main material is composed of polypropylene bag and polyethylene bag; according to the sewing method, it is divided into a seam bottom bag and a seam bottom bag. It is currently widely used as a packaging material for fertilizers, chemical products and other items. The main production process is to use plastic raw materials through extruded film, cutting, uniaxial stretching into flat yarn, and after warp and weft knitting to obtain products, generally called woven bags.